CN111683611B - Implants and methods for the treatment of Charcol's foot and other conditions - Google Patents

Abstract

A fixation system for fixing a bone structure is provided. It includes an internal fixation system having a shank plate subsystem, a shaft subsystem, and a midfoot plate subsystem. It also includes an external fixation system adapted to be connected to the internal fixation system and having a sole that provides a load-bearing platform under the patient's foot, enabling the patient to walk with the fixation system.

Description

Implants and methods for the treatment of Charcol's foot and other conditions

Cross Reference to Related Applications

The present application claims the benefit of U.S. provisional application Ser. No. 62/626,324, filed on 5/2/2018, the disclosure of which is expressly incorporated herein by reference in its entirety.

Technical Field

The present invention relates to implants and methods for treating various medical conditions generally involving the extremities of a mammal. One such condition is a deformity of the extremities of the human body known as the grass foot.

Background

The terms and descriptions contained herein are primarily within the field of orthopedics and will be apparent to those skilled in the field of orthopedics. Thus, only a brief description of the known subject matter in the art will be provided, as the details are well known to those skilled in the art. However, the present invention will be thoroughly described.

Injury or dysfunction of the peripheral nerves of the foot that lead to numbness or weakness (also known as neuropathy) can lead to a condition known as Charcol's joint disease or more commonly known as Charcol's foot. More specifically, when the feet of patients with neuropathy are damaged, the neuropathy may prevent them from feeling the damage. Without such a defense mechanism, which can cause the patient to feel pain, avoid continuing injury, and/or seek medical care, the patient will continue to walk on the injured foot. This typically exacerbates the injury and affects the surrounding areas of the foot, ultimately leading to deformities, disability, and even amputation that may occur in extreme cases.

A common symptom of late-stage shapede's foot is collapse of certain joints in the foot and leads to deformation of the foot. Surgical treatment typically involves realignment and fixation of various bones within the foot to correct such deformities.

Various general internal fixation systems including screws, plates, bolts, nails, etc. are known and may be used to correct the shack foot deformity. Similarly, various general external fixation systems including external frames, pins, wires, screws, etc. are also known and may be used to correct the shack foot deformity. Some challenges in the art are to construct a customized patient solution for the grass foot that includes internal fixation interacting with external fixation and providing a weight bearing platform for the affected limb, enabling the patient to walk soon after the surgery. The present invention provides a solution to these challenges and contemplates various novel and non-obvious combinations of implant modularity, interactions between internal and external fixation systems, and load bearing platforms.

Disclosure of Invention

There is provided a fixation system for fixing a bone structure, the fixation system having: an internal fixation system with one or more of a rod and plate system and a shaft system; an external fixation system. The rod plate system includes a rod secured to a plate, the rod adapted to be positioned in a bone canal, and the plate adapted to be positioned on bone adjacent the bone canal. The shaft system includes a shaft having a longitudinal axis, a slot on the shaft oriented in the direction of the longitudinal axis, and a hole on the shaft oriented at an angle to the longitudinal axis, the shaft further adapted to be positioned in a bone canal and configured to move two bone segments comprising the bone canal toward each other. The external fixation system includes a frame coupled to a sole having a bottom portion adapted to contact the ground.

The external fixation system also includes pins to connect the rod and plate system or shaft system to the external fixation system when the rod and plate system or shaft system is in the bone. Alternatively, the rod and plate system may be connected to the shaft system when both are located in the bone. The rods of the rod and plate system may be modularly comprised of a plurality of segments that may be joined by connections. The connection may be a threaded connection or a Morse taper connection. The plate of the rod and plate system includes a first side adapted to face the bone, an opposite second side, a length, a width, a plate axis along the length, and a protrusion extending from the first side. The projection has an opening in communication with a rod of the rod and plate system. The opening communicates with the rod by a threaded connection. The opening is cylindrical and has a longitudinal opening axis, wherein the opening is oriented such that the opening axis is at an angle to the plate axis. Finally, the shaft of the shaft system may modularly comprise a plurality of segments, each segment being joinable at a joint. The fixation system may also include a midfoot plate system attached to the bone, wherein the midfoot plate system includes a plate and fasteners that attach the plate to the bone.

Another embodiment of a fixation system provided for fixing bone structures includes an internal fixation system having a rod and plate system, a shaft system, and an external fixation system. The rod plate system includes a rod secured to the plate, the rod adapted to be positioned in the bone canal and the plate adapted to be positioned on bone adjacent the bone canal, wherein the plate further includes a first side adapted to face the bone, an opposite second side, a length, a width, a plate axis along the length, and a protrusion extending from the first side. The projection has a cylindrical opening with a longitudinal opening axis, wherein the opening is oriented such that the opening axis is at an angle to the plate axis. When both the rod and shaft systems are located in the bone, the rod and plate system is connected to the shaft system by at least one fixation element, and the external fixation system may also be connected to one of the rod and plate system or the shaft system.

Another embodiment of a fixation system for fixing a bone structure is provided having an internal fixation system and an external fixation system comprising one or more of a rod and plate system and a shaft system.

The rod plate system includes a rod secured to a plate, the rod adapted to be positioned in a bone canal, and the plate adapted to be positioned on bone adjacent the bone canal. The shaft system includes a shaft having a longitudinal axis, a slot on the shaft oriented in the direction of the longitudinal axis, and a bore on the shaft oriented at an angle to the longitudinal axis. The shaft is also adapted to be positioned in a bone canal and configured to move at least two bone segments through which the bone canal passes toward each other. The external fixation system includes a frame coupled to a sole having a shell and a bottom adapted to contact the ground, wherein the shell contains a liner. The liner further includes an inflatable bladder within the outer shell. The sole may be connected to the frame by an adjustable strut. The rod of the rod and plate system modularly includes a plurality of segments, each of which is engageable by a connection, wherein the connection may be a threaded connection, a Morse taper connection, or other type of connection.

The external fixation system further includes at least one pin to connect the external fixation system to a rod and plate system or shaft system, and to a frame of a sole, wherein the sole has a bottom adapted to contact the ground. The fixation system may also include a midfoot plate system attached to the bone, the midfoot plate system including a plate and a fastener.

Other features of the present invention will become more apparent upon review of the detailed description and drawings.

Drawings

The foregoing features of the invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a perspective view of a fully assembled fastening system of a preferred embodiment of the present invention, including an internal fastening, an external fastening, and a load bearing platform;

FIG. 1A is a perspective view of a human foot;

FIG. 2 is a side view of a rod component of the internal fixation system shown in FIG. 1;

FIG. 3 is a side view of a modular in-vivo connection mechanism that facilitates the rod component of an internal fixation system;

FIG. 4 is a side view of the alternative attachment mechanism shown in FIG. 3;

FIG. 5 is a side view of an alternative end of the rod component;

FIG. 6 is a top view of the web member of the internal fixation system shown in FIG. 1;

FIG. 7 is a side view of a web member;

FIG. 8 is a top view of an alternative embodiment of a web member;

FIG. 9 is a side view of the web member shown in FIG. 8;

FIG. 10 is a front exploded view of the connecting plate member shown in FIG. 8 with fasteners for attaching the plate member to bone;

FIG. 11 is a cross-sectional view of the web member of FIG. 8, taken along section line 11-11, connected to the rod member of FIG. 2, the rod member also being shown in cross-section for consistency;

FIG. 12 is a cross-sectional view similar to FIG. 11 but showing an alternative connection of the rod member to the plate member;

FIG. 13 is a top view of a human foot showing several assembled pole plate configurations with internal fixation systems;

FIG. 14 is a side view of the view shown in FIG. 13;

FIG. 15 is an exploded elevation view of the shaft member of the internal fixation system;

FIG. 16 is a partially exploded front view of the shaft member of FIG. 15, shown assembled with a plurality of fasteners for attaching the shaft member to bone;

FIG. 17 is a side view of a fully assembled shaft member secured to two bones prior to reduction;

FIG. 17A is a side view as shown in FIG. 17, depicting movement to reposition the space between two bones;

FIG. 18 is a top view of two axes in an implant foot;

FIG. 19 is a side view of the view shown in FIG. 18;

FIG. 20 is a top view of various internal fixation systems in an implant foot, including a plate rod configuration and a rod connected to a shaft;

FIG. 21 is a side view of the view shown in FIG. 20;

FIG. 22 is a perspective view of a midfoot plate member of the internal fixation system;

FIG. 23 is a top view of a midfoot plate member implanted in a foot and the other internal fixation systems depicted in FIGS. 20 and 21;

FIG. 24 is a top view of two shaft systems implanted in the foot and connected to an internal fixation system of an external fixation system;

FIG. 25 is a perspective view of a sole component as part of an external fixation system; and

figure 26 is an exploded perspective view of various components of the external fixation system, including the sole elements forming the load bearing platform.

Detailed Description

The following description of various embodiments of the present invention will be provided with reference to the human foot for convenience and explanation only. However, this portion of the body is merely exemplary, non-limiting and facilitates an intuitive interpretation of the invention, as aspects of the invention are also envisioned as being applicable to other skeletal structures.

Referring to fig. 1, a fixation system 10 for treating the shapede's foot and other limb deformities is shown. The fixation system 10 includes an internal fixation system 40 and an external fixation system 80. Internal fixation system 40 includes three general subsystems called a pole plate system 50, an axle system 60, and a midfoot plate system 70. The external fixation system 80 includes an optional weight bearing platform, referred to as a sole 400. Each system and some of its various internal and external components are modular and may be mixed, matched and used together or independently, as will be discussed in more detail below.

Referring to fig. 1A, a human foot includes a forefoot 12 including metatarsals 14 and phalanges 16, a midfoot 18 including three cuneiform bones 20, cuboid 22 and navicular 24, and a hindfoot 26 including talus 28 and calcaneus 30. For simplicity, and because anatomies are well known to those skilled in the art, further reference may be made herein to various parts of the foot without the accompanying reference numerals.

The directional and spatial anatomic terms also used herein are similarly well known to those skilled in the art. For example, the term "medial" generally refers to being closer to the midline of the body, while "lateral" generally refers to being farther from the midline of the body. Other terms such as "proximal," "distal," "front," "rear," "upper," "lower," and other such terms should have their ordinary and customary meaning in the art.

As used herein, the terms "rod" and "shaft" are selected to describe the longitudinal members of the internal fixation system for convenience and ease of explanation only and not for limitation. Accordingly, "rod" and "shaft" are intended to be non-limiting general terms that may include things such as bolts, nails, screws, posts, beams, and the like.

As an overview, fig. 2-14 depict components of a pole and plate system 50, the pole and plate system 50 being one of three subsystems of the internal fixation system 40. 15-19 depict components of shaft system 60, shaft system 60 being the second of the three subsystems of internal fixation system 40. Figs. 22-23 illustrate a midfoot plate system 70, which is a third subsystem of the internal fixation system 40. Figures 20, 21 and 23 illustrate various combinations of various internal fixation subsystems. And figures 24-26 depict components of an external fixation system 80.

Referring to fig. 2-5, the rod 100 includes a body 108 having a first end 104 and a second end 106, the second end 106 terminating in a planar surface 134. As alternatively shown in fig. 5, the second end 106 may terminate in a rounded surface 136. As will be discussed later, the rounded surface 136 is better suited to facilitate insertion of the rod 100 into a bone canal.

The rod 100 may be unitary and continuous from end 104 to end 106, or include two or more joined segments, such as a first segment 110 joined to a second segment 112 at a connection 102. The connection 102 generally represents various connection mechanisms that enable two pole segments to be joined together and will be discussed in more detail below.

The body 108 of the rod 100 may have a generally circular cross-sectional shape, or may have any other cross-sectional shape, such as oval, polygonal, or other shape, as may be suitable for various applications. The body 108 may also be roughened, knurled, or otherwise provided with any other surface topography known in the art for various purposes also known in the art to provide an improved surface for bone adhesion. Furthermore, the rod 100 or any segment thereof may be solid or hollow.

The first and second sections 110, 112 of the rod 100 are joined together at the connection 102. Fig. 3 shows a morse taper connection. Fig. 4 shows a threaded connection, both of which will be described in more detail below. Of course, other alternative connections are also contemplated. It is further contemplated that in the case of multiple segments of a rod, the same type of connection or different types of connections may be employed to join each two segments of rod 100 together, depending on a variety of factors, as known to those skilled in the art. Similarly, if it is desired to use more than one rod 100 in an implant, it is contemplated that one segmented rod may be assembled by one type of connection and another segmented rod may be assembled by another type of connection. The reason for this may be due to, for example, various details and advantages of one type of connection over another and the final performance of the assembled pole with different connection types.

As described above, fig. 3 depicts a morse taper type connection. The second pole segment 112 has a male end 118. The male end 118 includes a tapered shoulder 120 that tapers to a protrusion 122 that is smaller in diameter than the body 108. The first pole segment 110 has a female end 114 that includes a tapered opening 115 of substantially reduced diameter that opens into an internal bore 116. Typically, the female end 114 is sized to matingly receive the male end 118. Thus, shoulder 120 has a generally corresponding and dimensional relationship with opening 115 and similarly projection 122 with aperture 116. More specifically, as is known in the Morse taper art, the circumferential dimension of one or both of the shoulder 120 and the projection 122 of the male end 118 is slightly greater than the circumferential dimension of the opening 115 and the bore 116 of the corresponding female end 114. When the male end 118 is inserted into the female end 114, the interference in size results in a press fit, thereby locking the second pole segment 112 to the first pole segment 110.

If no rotational preference for axial alignment of the first segment 110 to the second segment 112 is desired, or no keying effect is desired, the Morse taper fit surfaces described above will all have a circular cross-section. Of course, if a bonding effect is desired, the cross-sectional shape of the mating surface may be elliptical, polygonal, or any other shape known in the art.

As an alternative embodiment, fig. 4 depicts a threaded connection 102 between a first pole segment 110 and a second pole segment 112. The female end 114 of the first pole segment 110 includes a bore 123 having internal threads 124. The male end 118 of the second pole segment 112 includes a corresponding protrusion 126 having external threads 128. The protrusion 126 having external threads 128 is configured to be threadably received in the threaded bore 123 of the female end 114. When assembled, the first pole segment 110 is securely connected to the second pole segment 112.

Referring to fig. 5, the rod 100 may have one or more through holes 130 configured to receive fasteners (not shown), such as bone screws or other fasteners known in the art. It will be apparent to those skilled in the art that the through bore 130 may be internally threaded to threadably receive a corresponding threaded fastener, or may be provided with any other connection mechanism known in the art. In other embodiments, the through-hole 130 is smooth and does not contain any form of connection mechanism. The through holes 130 may receive fasteners to facilitate securing the rod 100 within a medullary canal in which the rod 100 may be positioned. Alternatively, the through holes 130 may receive fasteners that are also connected to one or more other rods 100, which themselves may be positioned and secured relative to the other bones in the foot to provide fixation on those bones. In other embodiments, the aperture 130 may receive a fixation element from the external fixation system 80.

The slot 132 is depicted on the second end 106 of the rod 100 with its length oriented generally along the long axis of the rod 100. The purpose and function of the slot 132 will be discussed in more detail with reference to fig. 15-17A, wherein the shaft 200 has a relatively similar slot 240.

Referring to fig. 2, the first end 104 of the rod 100 includes a tab 138 having external threads 140 and a shoulder 142. As will be described in greater detail below, the tab 138, external threads 140, and shoulder 142 communicate with a connection plate 150 (fig. 11) to form an improved securing structure. In other embodiments, connection mechanisms other than threads are contemplated, such as interference fits, cross screws (fig. 12), nut-and-bolt, ratcheting mechanisms, and other connection methods known in the art.

In its contemplated embodiment, the rod 100 may be formed of any suitable material known in the art, such as titanium or other biocompatible material having mechanical properties suitable for the intended use of the fixation system 10. In addition, the rod 100 may be coated with any suitable biocompatible coating known in the art, such as hydroxyapatite, etc., or may be uncoated as desired to suit particular mechanical and clinical needs.

In contemplated embodiments of the invention, the rod 100 may be provided in various lengths and configured to provide axial stability to the bone in which it resides. In some embodiments, the rod 100 is configured to have a length such that the rod 100 extends from a portion of the metatarsal into the talus or calcaneus of the hindfoot to provide axial stability. The rod 100 may also be provided in a variety of diameters, such as a diameter of about 3mm, about 3.5mm, about 4mm, about 4.5mm, or any other diameter known in the art suitable for the intended use of the rod 100. It will be apparent to those skilled in the art that the surgeon may select one or more appropriately sized rods 100 in the operating room during the procedure, or may select and prepare rods 100 prior to the procedure.

Fig. 6-12 depict an embodiment of a connecting plate member 150 configured to facilitate connection between a rod, such as rod 100, and bone to improve the robustness and rigidity of the internal fixation configuration of fixation system 10. As described in the exemplary embodiments herein, plate 150 is attached to the metatarsal bones of a human foot. However, the description of the board 150 in the exemplary embodiment is merely for convenience and explanation and is not meant to limit the scope of the present invention to the exemplary embodiment. In other embodiments, plate 150 may be secured to bones other than the metatarsals of a human foot. For example, plate 150 may be secured to the metacarpal bone of a human hand or the bone of another person. The plate 150 may be generally parallelogram, square, rectangular, oval, or any other shape known in the art suitable for fixation to the bone to which the plate 150 is to be fixed.

Referring to fig. 6-12, the plate 150 includes a first side 152, a second side 154 opposite the first side 152, a thickness T extending therebetween, and a peripheral edge 156. In one embodiment, the plate 150 includes four lobes 158, each having a lobe edge 160 adjacent to the lobe 158 and a hole 162 extending through the thickness T of the plate 150. In other embodiments, the plate 150 may have more or fewer lobes 158, while in other embodiments, the plate 150 may have four lobes, wherein the lobes 158 include more or fewer apertures 162. The holes 162 are configured to receive fasteners, such as screws 164, and are generally circular, however other shapes of one or more of the holes 162 may also be used, such as slots. The aperture 162 includes a first flared portion 166 on the first side 152 of the plate 150 and a second flared portion 168 on the second side 154 of the plate 150. As will be appreciated by those skilled in the art, the second flared portion 168 is configured to receive a fastener head therein such that the fastener head may be partially or fully recessed within the plate 150. In addition, the combination of flared portions 166, 168 together enable the angled placement of a fixation element, such as screw 164, through plate 150. In various embodiments, the flared portions 166, 168 include a gradual taper or conical shape, a concave or stepped region, or a curved or rounded portion, or any other flare known in the art for receiving a fastener head. In other embodiments, flared portions 166, 168 may be omitted such that aperture 162 extends perpendicular to thickness T. In such embodiments, fasteners without protruding heads may be used. Additionally, it is contemplated that one or more of the holes 162 may be designed to receive a snap ring (not shown) or other mechanism to prevent the screw 164 from backing out of the plate 150. Such retraction mechanisms are well known in the art.

Referring to fig. 6, embodiments of the plate 150 may have various shapes and configurations. The plate 150 includes a major axis a, a minor axis C, a length L1 measured as a maximum length along the major axis a, and a width W1 measured as a maximum width along the minor axis C. The shape of the exemplary plate 150 is generally parallelogram, but the shape and configuration of the plate 150 may vary. For example, decreasing the length L1 or increasing the width W1 will result in a parallelogram shape that is more square-like. In other embodiments, the length L1 may be increased and the width W1 may be reduced, forming a rectangular parallelogram with one pair of opposing side peripheral edges 156 longer than the other pair.

The length L2 is the shortest distance between opposite portions of the peripheral wall 156 at the intersection of the major axis a and the peripheral wall 156, and the width W2 is the shortest distance between opposite peripheral walls 156 at the intersection of the minor axis C and the peripheral wall 156. In one embodiment, as shown in FIG. 6, the length L2 and the width W2 cooperate to provide a generally parallelogram shape. In some embodiments, the length L2 may be increased or decreased to provide a more rectangular or square shape, respectively. In other embodiments, the width W2 may be increased or decreased to provide a more square or rectangular shape, respectively.

The location of the lobes 158 may also vary. The length L3 is the length between the centers of two holes 162 all located on the same side of the minor axis C, and the width W3 is the width between the same holes 162. In some embodiments, the length L3 may be increased to produce a more diamond-like shape. In other embodiments, the length L3 may be reduced, which results in a shape that is less like a parallelogram. In some embodiments, the length L3 may be reduced to zero such that the two holes 162 are axially aligned along the minor axis C, i.e., the distance of the two holes 162 from the minor axis C is the same. In some embodiments, the width W3 may be increased to create a more square-like shape. In other embodiments, the width W3 may be reduced, which results in a more rectangular-like shape.

The position of each hole 162 within its lobe 158 relative to the lobe edge 160 may also vary. In some embodiments, each hole 162 may be disposed closer to its respective lobe edge 160, while in other embodiments, each hole 162 may be disposed further from its respective lobe edge 160. In other embodiments, if the plate 150 is made as a custom patient-matched implant requiring a change in configuration, the locations of the holes relative to their respective lobe edges 160 may be mixed and matched, for example, as may be desired based on various factors.

Referring to fig. 6, S1 is a shape of the periphery of the plate 150 along the C-axis. S2 is the shape of the perimeter of the plate 150 along the a-axis. These shapes S1, S2 are depicted as concave surfaces on the perimeter of the plate 150. S1, S2 may be complex formed splines resulting from transitions of radii of different lengths, or shaped in any other manner known in the art, including not having curvature and being straight. In some embodiments, the concavity of S1 and S2 may be greatly exaggerated toward the center of the plate 150, thus resulting in less material for the plate 150. In other embodiments, one or both of shapes S1 and S2 may be convex.

It will be apparent to those skilled in the art that the plate 150 has a variety of possible configurations. This further promotes the customizable nature of the plate 150. For example, the plate 150 may be provided with larger or smaller L3 and W3 dimensions to provide more or less distance between the holes 162, respectively. Similarly, other of the foregoing dimensions may be arranged to provide a varying plate 150 according to the preference of the surgeon or the needs of a particular patient. In some embodiments, various dimensions may be modified together to alter various aspects of the plate 150, such as the position of the lobes 158 relative to the peripheral edge 156.

With respect to the foregoing description, it should be understood that while various lengths and widths are depicted in FIG. 6 on only one side of axis A or C, such description is for clarity and explanation only and is not meant to be limiting. Thus, for any particular length or width described, there are identical aspects and dimensions on opposite sides of axis a or C, and modifications can be made as described above. It should also be appreciated that the foregoing dimensions need not be symmetrical and may vary from one side of axis a or C with respect to the other side of axis a or C, respectively.

With continued reference to fig. 6-12, the plate 150 may include a protrusion 180 extending generally orthogonally away from the first side 152 of the plate 150. The purpose of the tab 180 is to enable the plate 150 to be connected to the rod 100. The protrusion 180 includes an inner opening 182 that may be configured to receive the first end 104 or the second end 106 of the rod 100 of fig. 2-4, and further includes an outer face 184 (fig. 10). In one embodiment, the internal opening 182 may be formed with internal threads 186 to communicate with the external threads 140 of the tab 138 of the stem 100 (see fig. 2 and 11). In some embodiments, the inner opening 182 is a blind hole (see, e.g., fig. 7 and 9), while in other embodiments, the inner opening 182 may extend completely through the protrusion 180. In other embodiments, the inner opening 182 may be unthreaded and the connection between the opening 182 and the rod 100 may be a Morse taper type connection.

Referring to fig. 2 and 11, it will be apparent to those skilled in the art that, during assembly of the lever 100 to the plate 150, when the lever 100 is inserted into the opening 182 to a sufficient depth, the shoulder 142 of the lever 100 will contact the face 184 of the tab 180 of the plate 150, thereby stopping the movement of the lever 100 into the tab 180 and ensuring that the lever 100 does not exceed the tab 180.

In other embodiments, the plate 150 and optional rod 100 may be configured with other structures or mechanisms known in the art that facilitate connection of the plate 150 to the rod 100.

Referring to the exemplary embodiment of fig. 12, the rod 100 does not have threads 140 on its tab 138, but has a through hole 178 extending transversely through the tab 138. The plate 150 is provided with a partially threaded transverse bore 170 having threads near the second side 154 of the plate 150. The transverse bore 170 is configured to receive a partially threaded screw 176 and is in threaded communication with the screw 176 in the region shown at 172. After the rod 100 is inserted into the opening 182 of the protrusion 180, the through-hole 178 of the rod 100 is axially aligned with the transverse bore 170. Optionally, this alignment may be further facilitated by having mating keyed surfaces on the tab 138 and the opening 182, as is known in the art. A screw 176 is then inserted into the bore 170 and through the through bore 178 of the rod 100 and is threadably secured to the plate 150 at region 172. A portion of the hole 170 may be countersunk or otherwise formed to fully or partially receive a head of a fastener, such as the head 174 of a screw 176, to enable the head 174 to sink into the protrusion 180 of the plate 150.

Referring to fig. 6-8 and 11, an opening 182 in the tab 180 of the plate 150 is formed about the longitudinal axis D (fig. 7). In this embodiment, axis D is in the same plane as axis A, which is defined by section line 11-11. Axis D travels through point P, which is a point in space within opening 182. Line E is a reference line drawn parallel to axis a of plate 150 and is offset from axis a by also traveling through point P. As best seen in fig. 11, where the rod 100 is assembled with the plate 150, the angle α is the angle between the axis D and the line E, representing the angle between the rod 100 and the plate 150. It will be apparent to those skilled in the art that the angle α may be in the range of about 5 ° to about 30 ° relative to line E, or may be any other angle that may be suitable for a variety of clinical needs. In an alternative embodiment (not shown), the angle α may even be a negative angle, and in this case the plate 150 will be shaped to accommodate the rod 100 through its second side 154 and protruding above that second side 154. For example, the plate 150 may have an opening through its thickness T to accommodate the rod 100, or the peripheral edge 156 of the plate 150 may be concave in shape to make room for the rod 100 to pass through an adjacent plate 150.

In other alternative embodiments, the orientation of the rod 100 to the plate 150 may be different. For example, axis D may be oriented at an angle relative to a plane formed by cross-sectional line 11-11. This is shown in fig. 6 with reference to axis D'. Axis D' is represented at an angle β relative to axis a. Such as angle alpha, angle beta represents the angle at which the rod 100 is assembled with the plate 150. Of course, many other alternative configurations are also conceivable.

It is further contemplated that the openings 182 in the protrusions 180 may be designed at different angles as described above in order to achieve angulation of the rod 100 with the plate 150. Or it will be apparent to those skilled in the art that the protrusions 180 themselves may be designed on the plate 150 at different angles and configurations.

Alternatively, the plate 150 may be flat (e.g., as shown in fig. 7) or curved (e.g., as shown in fig. 9). The curvature of the plate 150 in fig. 9 is along the long axis a. However, it will be apparent to those skilled in the art that many other bends and shapes of the plate 150 are possible, as determined by different considerations such as manufacturability or various clinical factors such as the anatomy of a particular patient. Furthermore, it is contemplated that the plate 150 may be provided as a rigid, inflexible plate, or alternatively, as a deformable plate, to enable intraoperative bending as desired.

The plate 150 may be formed of any one or more suitable biocompatible materials known in the art, such as titanium, PEEK, or other biocompatible materials having mechanical properties suitable for the intended use of the plate 150. The plate 150 may also be coated in whole or in part with any suitable biocompatible material coating known in the art.

For ease of reference, when the rod 100 is assembled with the plate 150, this may also be referred to as a rod plate configuration, and thus the rod plate system 50 may include one or more rod plate configurations.

Fig. 13 and 14 depict an embodiment of a rod board system 50, in this case comprising a plurality of rod board configurations implanted in a human foot. Of course, it will be readily appreciated that the number of rod plate configurations required for a particular patient may be determined by the surgeon.

In use, implantation of the rod-like construct may begin by first aligning and preparing each target bone for fusion. An appropriately sized opening into the medullary canal of the target metatarsal is made in the dorsal aspect of its central portion. The guidewire is then passed through the opening, through the medullary canal, and on through the other bones to be fused. Alternatively, the guidewire may be threaded to the talus or calcaneus. A hollow drill bit of appropriate size is then passed through the guide wire and used to create a passageway in the bone to accommodate the rod 100.

A rod 100 having a length selected and corresponding to the drilled passage is connected to the plate 150. The second end 106 of the rod 100 is then inserted into the opening and through the channel until the tab 180 of the plate 150 rests within the dorsal opening in the metatarsal. Alternatively, the plate 150 may be shaped to conform to the topology of the metatarsal after insertion or in advance. In other embodiments, a rigid pre-contoured plate 150 may be used. Once the lever plate is configured in place, the plate 150 is then fixedly attached to the metatarsal using fasteners such as screws 164.

15-17A depict an exemplary embodiment of an axle system 60 as a subsystem of internal fixation system 40. The shaft system 60 may be used alone or in combination with other systems to facilitate alignment, reduction, and fixation of bones.

The primary component of the shaft system 60 is a shaft 200. The shaft 200 may be a unitary device or a modular device made up of individual segments that may be joined together, thus enabling customization of the shaft 200. Referring specifically to fig. 15, the shaft 200 is modular and includes segments referred to as a cover 202, an intermediate spacer 204a, an intermediate spacer 204b, and a base 206. The segments may each be joined to one another at a connection 203 (shown as joined in fig. 16-17A). Connection 203 may be a threaded connection, a Morse taper type connection, or any other suitable connection known in the art. It should also be appreciated that one or more different types of connections 203 may be used to assemble the shaft 200.

The cap 202 is a hollow body that includes a hole 215. The cap 202 also includes a first end 210 and a second end 212, the first end 210 having a rounded terminal portion 214 that facilitates insertion of the shaft 200 into bone during implantation, and the second end 212 having an internal thread 216 in the bore 215 to enable the cap 202 to be connected to another matable section of the shaft 200. The cap 202 also has a transverse through hole 218 to receive a fixation element 220 (fig. 16) to secure the cap 202 and thereby assist in securing the shaft 200 to bone. Further details regarding the alternative configuration and use of the vias 218 will be discussed in greater detail later with reference to the base 206.

The intermediate spacers 204a and 204b each have a similar configuration, except that the spacer 204a includes a through hole 218, while the spacer 204b does not have any such through hole. The spacers 204a, 204b also each have a first end 222, an opposite second end 224, and an aperture 215 extending therebetween, such that they are hollow. On the first end 222, there is a protrusion 225 with external threads 226. The external threads 226 are configured to mate with the internal threads 216 to enable a secure connection 203 therebetween, and thus between any one of the spacers 204a, 204b and the cap 202. It is apparent from this description that the intention is to make possible easy interchangeability and interconnectivity of the different segments.

The base 206 also has a first end 232, an opposite second end 234, and an aperture 215 extending therebetween, such that it is hollow. For purposes of interchangeability, the base 206 has a similar tab 225 on its first end 232 with external threads 226, as described above with reference to the other paragraphs. Also shown is the base 206 with a through hole 218 to enable connection to bone. The base 206 also has a slot 240 therethrough at its second end 234 to facilitate bringing together two bone segments, also referred to as reduction, as will be discussed in more detail below. Finally, the base 206 has internal threads 248 at the second end 234 thereof. These internal threads 248 are configured to mate with the external threads 226 of the respective segments and with the external threads 256 of the plug 208. Notably, the internal threads 248 may extend deeper into the bore 215 of the base 206 than the comparable internal threads 216 in the other segments. This is because the internal threads 248 are also configured to receive the plug 208.

Also for interchangeability, the plug 208 includes a body 255 having external threads 256 similar to external threads 226 on other segments of the shaft 200, a compression element 260, and an instrument engagement region 265. The insertion of the plug 208 into the second end 234 of the base 206 and its movement through the aperture 215 along with the slot 240 and the use of the fastener 242 (fig. 16) enables resetting, as will be discussed in more detail below.

Referring to fig. 16-17A, to perform a reduction, one bone segment must be stationary and an adjacent bone segment must be moved toward the stationary bone segment. In this embodiment, the bone B1 is a static bone. The shaft 200 is secured to the bone B1 by a screw 220 positioned through a through hole 218 in the base 206. Notably, the through hole 218 also provides further variations of the method of securing the shaft 200 to bone, as described below.

It is recognized that there are at least two common methods of fixing the shaft 200 in space relative to bone, among various other methods known in the art. In one such common method, this is accomplished by securing the proximal bone portion Bp to the shaft 200. In another common method, this is accomplished by stapling the shaft 200 between two bone segments.

Referring to the first method, when the shaft 200 is positioned in a bone canal (fig. 17), a hole 230 is drilled from the proximal bone surface Bp of the proximal bone B1 to the exterior of the shaft 200. The hole 230 is coaxial with the through hole 218 and is sized to allow the head of the screw 220 to pass. The screw 220 is then inserted through the hole 230 and threaded into the threaded form of the through hole 218. As is well known in the art, the screw 220 need not extend all the way through the base 206, so long as there is sufficient threaded engagement in the first contact area between the screw 220 and the base 206. Of course, if more threaded engagement is desired, the screw 220 may be further advanced to threadedly engage the base 206 at its second contact area with the base 206. It will be readily appreciated that the method just described from bone surface Bp may be similarly accomplished from the opposite distal bone surface Bd. For this reason, it is desirable to have a fully threaded through hole 218.

With respect to the second method of fixing the shaft 200 in space relative to the bone, the objective is to have the screw 220 enter through the hole 230, extend completely through the shaft 200, and threadably grasp the bone portion Bd. While this approach may better require the throughbore 218 to be unthreaded, the threaded form of the throughbore 218 may continue to be employed in order to increase the variability of use of the shaft 200. Of course, having described the foregoing, it will be readily appreciated that various alternatives and permutations of the above described configuration of structures and uses may be employed. In addition, it should be noted that the through hole 218 has the same characteristics as the through hole 130 of the lever 100.

With further reference to fig. 16-17A, in the case of a reduction, the bone segment that will move toward the stationary bone segment B1 is the movable bone segment B2. Of course, motion is generally considered relative. In a similar manner as described for threading screw 220 through throughbore 218 of base 206, partially threaded screw 242 is threaded through slot 240, particularly through slot region 244 of first end 232 furthest from base 206, and into bone B2. The plug 208 may be introduced into threaded engagement with the internal threads 248 of the second end 234 of the base 206 and positioned at the slot region 244 either before or after insertion of the screw 242. A driver (not shown) is then engaged to instrument engagement region 265 of plug 208 and actuated to rotate plug 208 in direction F (fig. 17A) to translate plug 208 to slot region 246 by means of the translational component of the threaded rotation. In so doing, compression element 260 of plug 208 pushes screw 242 linearly along slot 240 from slot region 244 a distance M to slot region 246. Thus, this pushes bone segment B2 the same distance M toward bone segment B1, with bone segment B1 fixedly connected to base 206 by throughbore 218, thus resulting in a reduction.

Those skilled in the art will readily appreciate that the above-described reset mechanism (including elements such as slot 240 and plug 208) may be positioned on any other segment or segments of shaft 200 to increase the variability of the segments of shaft 200. Of course, other means may be required to rotate or advance the plug 208 in the event that its instrument engagement region 265 is not accessible, as in the above-described embodiments.

Although slot 240 has been described in the context and function described with reference to shaft 200, as previously described, a somewhat similar slot 132 is positioned on rod 100 (fig. 5). The particular mechanism of resetting using slot 132 will be different from that described for slot 240, but such other ways of performing resetting are known in the art. For example, referring to fig. 24, if pin 310 is inserted into one bone through slot 132 of rod 100 and screw 220 is inserted into the other bone through hole 130 of rod 100, the surgeon may manually grasp and translate pin 310 and screw 220 to each other, thereby bringing the two bones together.

The ability to rotationally align one segment of the shaft 200 relative to another segment of the shaft 200 to a desired position is an engineering function with many different solutions known in the art for a variety of purposes. For example, referring to fig. 16, it may be desirable to have a through hole 218 on the cap 202 oriented 30 ° from either direction as shown. Similarly, on the same axis 200, it may be desirable for the through holes 218 on the spacer 204a to be oriented 15 ° from their illustrated position. One way to achieve this desired alignment of the through-hole 218 in the assembled shaft 200 is to have keyed, timed or precision threads 216, 226 that enable the intended rotational assembly to result in the desired alignment.

The ability to aim and insert the screws 220, 242 into their respective positions in or through the rod 100 and shaft 200 is also an engineering function with a variety of different solutions known in the art. For example, when the shaft 200 is inside a bone, an aiming clip is known to facilitate positioning and identify the orientation of the through hole 218. The rod 100 and shaft 200 may be configured to mate with such an aiming fixture.

As previously noted with respect to rod 100, shaft 200 and the various other elements described above may be formed from any suitable material known in the art. For example, the shaft 200 may be formed of titanium or other biocompatible material having mechanical properties suitable for its intended use. In addition, the shaft 200 may be coated with any suitable biocompatible coating known in the art, such as hydroxyapatite, etc., or may be uncoated as desired to suit particular mechanical and clinical needs.

It will be apparent to those skilled in the art that the shaft 200 may be solid rather than hollow, and the rod 100 may be hollow rather than solid. Of course, various other adjustments may then be made to their respective features to cause those features to retain their respective intended functions. For example, if the shaft 200 is solid rather than hollow, the second end 234 of the base 206 would still remain a hollow passageway to enable the plug 208 to travel therethrough to effect repositioning.

Referring to fig. 18 and 19, two shafts 200 of the shaft system 60 are shown implanted in a human foot. The medial shaft 200 is assembled from a cap 202, followed by two spacers 204a, and then a base 206, and oriented such that the base 206 is located in the first metatarsal, and the cap 202 is located in the talus. The outboard shaft 200 is assembled from another cover 202 and a base 206. Oriented such that the base 206 is in the calcaneus and the cover 202 is in the cuboid. Each shaft 200 is depicted as being fixed in place on the bone by a respective screw 220, 242.

First, each bone to be fused is manually aligned and ready to receive shaft system 60. For example, to implant the medial shaft 200, the first metatarsal phalangeal joint is exposed through a dorsal incision. A guide wire is then introduced near the center of the metatarsal head to guide reaming of the medullary canal, through the metatarsal body, the medial cuneiform navicular, and into the talar neck. Reaming is then repeated over the guidewire until a root canal having an appropriate inner diameter is formed through the bone to accommodate the shaft 200. Of course, it is recognized that the various anatomical landmarks and sizes of the bone will ultimately determine the choice of root canal diameter and length, and thus the diameter and length of the shaft 200 to be used therein, and which segments of the shaft 200 should be selected and the order in which they are assembled.

Before the shaft 200 is inserted, it may be connected to an aiming jig (not shown). The aiming jig protrudes over the shaft 200 at the location of the associated through hole, such as hole 218, thus enabling the surgeon to accurately place a screw 220 through the aiming jig directly into or through each aiming hole 218, e.g., as the case may be, after placement of the shaft 200 in the reamed bone canal.

Once the target jig is attached to the medial shaft 200, the medial shaft 200 is inserted into the reamed bone canal. The screw 220 is then passed through the clamp and through hole 218 of the cap 202 in the talus. The screw 242 is then passed through the clamp and through the slot 240, the slot 240 being located in the first metatarsal in this embodiment. The plug 208 in the second end 234 of the base 206 is then rotationally actuated to translate axially along the slot 240, compressing all bone between the screw 242 and the screw 220 along the shaft 200 to a desired orientation, at which point the other screws 220 will be inserted through the shaft 200 to lock the compressed bone in place relative to the shaft 200. Alternatively, some or all of the compression may also be performed by other techniques known in the art.

In view of the foregoing, the preparation of the bone, the selection, assembly and insertion of the lateral shaft 200, and the reduction and fixation of the associated bone will be apparent to those skilled in the art.

Referring to fig. 20-21, an implant combination of a rod and plate system 50 and an axis system 60 is depicted. Specifically, there are two lever plate configurations and two shafts 200. Notably, the rod 100 can be connected to the shaft 200 and described as such. This may be accomplished using screws 220 or by other means. It will be apparent to those skilled in the art that any number, combination and configuration of rod and plate constructions and shafts may be employed, and may also be connected to each other at different points as desired to address various clinical needs.

Fig. 22 depicts a midfoot member in the form of a plate 280 having screw holes 281, the screw holes 281 being adapted to receive screws 282 (fig. 23) that attach the plate 280 to bone. Plate 280 is well known in the art. The plate 280 may be malleable so that it can be shaped in situ to conform to the target anatomy to which it is to be attached, or provided in a variety of generic rigid shapes, or custom manufactured by patient matching techniques. Which is intended to be used alone or in combination with one or more systems and subsystems of the fixation system 10.

Fig. 23 depicts a plate 280 implanted in the foot in combination with a rod plate configuration and shaft 200, wherein some rods 100 and shafts 200 are interconnected. The possibility of combining all these subsystems provides increased variability and flexibility to meet a wider variety of clinical needs.

Fig. 24 depicts an internal fixation subsystem, i.e., shaft system 60, connected to an external fixation system 80. The external fixation system 80 includes one or more frames 302, each having a plurality of openings 304, a plurality of connectors 306, and pins 310. The pin 310 is depicted as partially threaded on its distal end, and may also optionally be unthreaded or fully threaded, as is known in the art. The basic external fixation system 80 is also well known in the art.

It is noted that one aspect of the present invention is the connection of the external fixation system 80 to the shaft system 60, as shown in fig. 24. Specifically, the frame 302 is connected to the shaft 200 using pins 310 inserted through the connector 306. Thus, it should be apparent that many other configurations, arrangements, and connections of external fixation system 80 to one or more of the certain subsystems of internal fixation system 40 are possible. For example, the external fixation system 80 may be connected to the implanted rod plate system 50.

The additional ability to combine and connect the external fixation system 80 with the various subsystems of the internal fixation system 40 further increases the variability and flexibility of the overall fixation system 10 to treat a wider variety of clinical needs.

Fig. 25 depicts sole component 400 of external fixation system 80. Sole component 400 is intended for use in conjunction with external fixation system 80 and is intended to provide a load-bearing platform under a patient's foot to enable a patient with fixation system 10 to walk.

The sole 400 includes a shell 402 adapted to retain a removable liner 404 therein. From front 410 to back 412, housing 402 has a top surface 406, side walls 407, and a bottom surface 408 that span housing 402 from front 410 to back 412. Bottom surface 408 is the surface that contacts the ground when the patient walks while wearing fixation system 10. Thus, its shape, texture and material may be adapted as known in the art to promote safer walking. For example, the bottom surface 408 may be made of or coated with rubber to increase the coefficient of friction between the sole 400 and the ground, thereby reducing the chance of a patient slipping while walking with the binding 10. Other embodiments are also contemplated to accomplish this.

The contour of the bottom surface 408 may be a complex series of continuous curves, such as a tighter curve toward the rear face 412, which may be referred to as a heel strike area, ultimately transitioning to a gradual curve toward the front face 410, with the forefoot rolling on gait. Of course, other shapes are also contemplated.

Liner 404 may include an inflatable bladder (not specifically shown) and be filled with any suitable fluid. The bladder may have a valve (not specifically shown) through which air or other fluid may be introduced or exhausted to achieve optimal density and size to support a particular weight or pressure requirement. The liner 404 may optionally be housed in a fabric casing (not specifically shown). The housing is moisture absorbent and sweat permeable and machine washable for easy cleaning and maintenance. The housing may also be removable by a zipper, hook and loop fasteners, snaps, and the like.

The sole 400 also has slots 424 that enable it to be connected to the frame 302 (fig. 26), as will be discussed in more detail below. As one skilled in the art can readily appreciate, the slot 424 may be formed in the material of the housing 402 or may be a solid tube secured inside or outside the housing 402.

Fig. 26 is an exploded view of certain components of the external fixation system 80 for assembling the sole 400 to the frame 302. More specifically, the connectors 306 have threaded openings 307 on each face thereof, thereby enabling them to be connected to the frame 302 and other components using bolts 308, thus making them versatile.

The struts 426 serve to connect the sole 400 to the frame 302. The strut 426 has an eyelet 428 to enable this connection. For example, after the connector 306 is connected to the frame 302 with the bolts 308, the eyelets 428 of the posts 426 will be aligned with the connector 306, and additional bolts 308 will be passed through the eyelets 428 and threaded into the connector 306, thereby caulking and securing the posts 426 to the frame 302. The strut 426 should also be connected to the sole 400 in any of a variety of ways known to those skilled in the art. For example, the posts 426 may be inserted and glued into the slots 424.

The strut 426 may be of unitary construction or may comprise two or more components such that the strut 426 is capable of expanding and compressing and being secured in place at a desired length. The strut 426 may also be made from a variety of materials, from hard metals to more resilient materials, which may further help absorb the impact forces during gait.

Having thus described the invention in detail, it is to be understood that the foregoing description is not intended to limit the spirit or scope thereof. It will be understood that the embodiments of the present disclosure described herein are merely exemplary and that a person skilled in the art may make any variations and modifications without departing from the spirit and scope of the present disclosure. All such variations and modifications, including those discussed above, are intended to be included within the scope of the present disclosure.

Claims (15)

1. A fixation system for fixing a bone structure, comprising:

an internal fixation system, comprising:

rod and plate system, and

a shaft system; and

an external fixation system;

wherein the pole plate system comprises:

a rod directly secured to the plate, the rod adapted to be positioned in the bone canal, the rod modularly comprising a plurality of segments, each segment being engageable by a connection, and the plate adapted to be positioned on bone adjacent the bone canal; wherein the shaft system comprises a shaft having a longitudinal axis, a slot oriented on the shaft in the direction of the longitudinal axis, and a hole oriented on the shaft at an angle to the longitudinal axis, the shaft further adapted to be positioned in a bone canal and configured to move two bone segments comprising the bone canal toward each other; and is also provided with

Wherein the external fixation system comprises a frame connected to a sole having a bottom adapted to contact the ground.

2. The fixation system of claim 1, wherein the external fixation system further comprises a pin, and the external fixation system is connected to the rod plate system or shaft system via the pin, and the rod plate system or shaft system is located in a bone.

3. The fixation system according to claim 1, wherein the rod and plate system is connected to an axis system when both are located in bone.

4. The fixation system of claim 3, further comprising a midfoot plate system attached to the bone, the midfoot plate system comprising a plate and a fastener.

5. The fixation system of claim 1, wherein the connection of the plurality of segments of the rod and plate system is a threaded connection or a morse taper connection.

6. The fixation system according to claim 1, wherein the plate of the rod and plate system comprises a first side adapted to face the bone, an opposite second side, a length, a width, a plate axis along the length, and a protrusion extending from the first side.

7. The fixation system according to claim 6, wherein the protrusion comprises an opening in communication with a rod of a rod and plate system.

8. The fixation system according to claim 7, wherein the opening in the projection communicates with the rod by a threaded connection.

9. The fixation system according to claim 7, wherein the opening is cylindrical and has a longitudinal opening axis, and the opening is oriented such that the opening axis is at an angle to the plate axis.

10. The fixation system according to claim 1, wherein the shaft of the shaft system comprises a plurality of segments modularly, each segment being engageable by connection.

11. A fixation system for fixing a bone structure, comprising:

an internal fixation system having:

rod and plate system, and

a shaft system; and

an external fixation system;

wherein the pole plate system comprises:

a rod secured to the plate, without a separate connecting member therebetween, the rod being adapted to be positioned in the bone canal, the rod of the rod-and-plate system modularly comprising a plurality of segments, each segment being engageable by connection, and

the plate is adapted to be positioned on bone adjacent to a bone canal;

the plate also has a first side adapted to face the bone, an opposite second side, a length, a width, a plate axis along the length, and a projection extending from the first side, the projection having a cylindrical opening with a longitudinal opening axis, and the opening being oriented such that the opening axis is at an angle to the plate axis;

Wherein the rod and plate system is connected to the shaft system by a fixation element when both are located in the bone; and is also provided with

Wherein the external fixation system is connected to one of a rod and plate system or an axle system.

12. The fixation system according to claim 11, wherein the connection of the plurality of segments of the rod and plate system is a threaded connection or a morse taper connection.

13. The fixation system of claim 11, wherein the external fixation system further comprises a pin, and wherein the pin connects the external fixation system to one of the rod and plate system or shaft system.

14. The fixation system according to claim 13, wherein the external fixation system further comprises a frame coupled to a sole having a bottom adapted to contact the ground.

15. The fixation system of claim 11, further comprising a midfoot plate system attached to the bone, the midfoot plate system comprising a plate and a fastener.